Introduction

Global Warming
Myths?

Do sunspots and
gamma cosmic rays (GCR) influence global temperatures? Is it true
that volcanoes put out more carbon dioxide than all the manmade
carbon emissions put together? Is the world soon to be flooded with
higher sea levels? Let's look at the real data and
determine what is true and what is false.

Rich Deem

I get many questions about the science behind the global warming
controversy. It seems that many conservatives feel compelled to deny the
connection between global warming and greenhouse gases (although one would
be hard-pressed to find anyone who would deny that carbon dioxide and
methane are greenhouse gases that are increasing rapidly in our atmosphere).
Global warming deniers often cite data that is skewed or even false in order
to support their claims. Radical environmentalists exaggerate claims to
promote their political agendas. This page is an attempt to address some standard
myths that have arisen among those who deny or exaggerate how humans are responsible for
earth's warming temperatures. As with the main
global warming page, all the original data is cited and presented so
that you can confirm the validity of the science.

Rodney Viereck, NOAA Space Environment Center, brought up an idea that sea surface temperature (SST)
correlated with sunspot number.1 However, the data just didn't seem quite
right. Since sunspots cycle over
a short period (ten years), it seemed that Mr. Viereck had used some really
bad data. So I downloaded the sunspots data for the entire
period of 1880 to 2006. This is what it looks like (global surface
temperatures in blue and sunspots in green). The "correlation" obviously
disappears when one examines the data. Although the number of sunspots has
risen, the number has remained constant since 1960, the period in which global
temperatures have risen the most. Obviously, the correlation doesn't really hold
up.

Danish researchers Henrik Svensmark and Eigil Friis-Christensen have
demonstrated that cosmic rays can cause cloud cover to vary as much as 2%
within a period of 5 years. This produces a change in the heating of the earth's surface
by up to 1.2 W/m2. The claim is that since, the IPCC has
estimated that CO2 emissions since the Industrial Revolution have
caused an increase of 1.6 W/m2,2 it is possible that cosmic rays
have accounted for 75% of global warming. The problem is that the latest Svensmark and Friis-Christensen data contradicted much of their earlier
work. Like the sunspot data, when the data is plotted over many decades, the
trend disappears quite well. Of course, solar activity and GCR do impact
climate in the short term (over their 10 year cycles). The problem is that
there are no long term trends for either, whereas there are long term trends
for climate.

A more recent study examined the effects of cosmic rays on the
"ion-aerosol clear-air" hypothesis, which suggests that increased cosmic
rays cause increases in new-particle formation, cloud condensation nuclei
concentrations (CCN), and cloud cover. However, the new paper showed that
the magnitude of the ion-aerosol clear-air mechanism was two orders of
magnitude too small to account for the observed changes in cloud properties,3
demonstrating that it could not be the cause of the current global warming
trend.

Volcanoes produce more carbon dioxide than all
carbon emissions produced by humans

The claim is that volcanic action around the world in one day spews forth
more greenhouse gases than all of man's activities in one year. The claim is
completely false. In fact, all the volcanic activity over the entire world
for one entire year emits 130-230 teragrams carbon dioxide (http://en.wikipedia.org/wiki/Volcano).
In contrast, human activities produce over 7000 teragrams/year (1
petragram=1000 tergrams) (See Figure 3, right). So, volcanoes emit only 3% the amount that humans do.
In fact, human activity exceed that of volcanic activity early in the
Industrial Revolution (by 1870).

Urban heat island effects account for global warming

Many skeptics claim that the location of temperature measuring stations
near cities results in readings that are artificially inflated from the real
temperature measurements. This problem is known as urban heat island effects. These
effects are real but local, and have a negligible influence (less than
0.006°C per decade over land and zero over the oceans)4 on
global temperature values. In addition, the largest changes in global
temperatures have been recorded north of 60° latitude, where there are
no large cities at all (Figure 4).

Global warming will result in a sea level rise of 9 feet
this century

The IPCC WGI Fourth Assessment Report indicates an observed sea level
rise of 0.18 m (7 in) per century for the period of 1960-2003. However, the
rate is increasing rapidly, such that the rate for the last ten years of the
period are nearly double (0.31 m/century). The IPCC puts the projected sea
level rise for the 21st century at 0.26 – 0.59 m (10-18 in). Sea levels have
risen 0.2 m (8 in) in the last 150 years (Figure 5).

Global warming will result in increased temperatures of 9°C

The IPCC WGI Fourth Assessment Report puts the amount of temperature
increase at 1.8°C/century if global carbon dioxide concentrations remain at
year 2000 levels (extremely unlikely). If fossil fuel usage increases
dramatically (probably also unlikely), the projected increase would be 4.0°C/century.
The most likely value would be 2-3°C, most of which would occur in high
latitudes and/or during the winter months.

Global Warming has stopped since temperatures have been stable for
several years

Although surface temperatures have risen rapidly in the last 100 years,
in the last 8 years, temperatures have leveled off. Does this mean that
global warming has stopped? The past temperature recordings have shown
global warming occurs in spurts, with periods of little or no change for up
to 30 years. The fact that temperatures have not risen rapidly in the last 8
years is not unexpected, since we are currently at the lowest point in the
Sun's luminosity cycle (Figure 6).3 The figure
shows that surface temperatures have generally peaked near solar irradiance
peaks and have leveled off during solar irradiance troughs. It is also
interesting to note that the overall trend is for decreasing solar
irradiance during a time of increasing temperatures. It's a good thing solar irradiance is not increasing
during this time!

Conclusion

Many myths surround climate change science. The fact that climate change
has become a political issue has not helped matters. As conservatives and
liberals tend to line up at the extremes and promote their own hype, the
voice of reason and science tends to be drowned out. At this point, it seems
very unlikely that a natural cause is behind our world's increasing
temperatures. Even so, the scare tactics of radical environmentalists and
liberal politicians does nothing to prioritize our response to global
warming.

Help us add to this page

If you are a global warming skeptic or radical environmentalist, send in your best ideas so I can
research the data to present on this page. Please e-mail your suggestions to
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